object CollectionOpsDemo {
  def main(arg: Array[String]): Unit = {
    val clubs = List(
      ("编程社",35),
      ("文学社",28),
      ("篮球社",42),
      ("话剧社",25)
    )
    val activeClubs = clubs.filter {case (_, count) => count >= 30}
    val clubFormats = activeClubs.map { case (name,count) =>
      s"$name($count 人)"
    }
    println("活跃社团")
    clubFormats.foreach(println)
  }
}